<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN"
"http://www.w3.org/TR/html4/strict.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" lang="en">
	<head>
		<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
		<title></title>
		<style type="text/css">
			*{
				padding: 0;
				margin: 0;
			}
			.one{
				border: 1px solid red;
				margin-right: 50px;
			}
			.two{
				border: 1px solid blue;
				margin-left: 30px;
			}
		</style>
	</head>
	<body>
		<!--行级元素只有左右外边距没有上下外边距-->
		<span class="one">我们都是span标签</span><span class="two">我们都是span标签</span>
	</body>
</html>
